Recombinant protein expression, purification, and initial biochemical characterization is rapidly becoming the rate-limiting step in testing biological hypotheses related to complex signaling networks. Extensive sequence databases, sophisticated algorithms for domain prediction, and various high-throughput technologies such as gene array analysis provide a wealth of initial data easily converted into testable hypotheses. Conventional biochemical techniques carried out in individual laboratories are becoming increasingly incapable of providing the numerous biochemical reagents and associated analyses required to test this rapidly expanding universe of hypotheses. This proposal seeks to address this dilemma for the Projects of the PPG by providing a Protein Core capable of rapidly producing, purifying, and functionally characterizing the numerous and diverse proteins and domains required for the proposed studies. The Protein Core will rely heavily on automation of reagent handling and miniaturization of biological assays amenable to high-throughput processing. In particular, the Protein Core will house robotics for the rapid generation of arrayed clones and the automated purification of analytical amounts of arrayed proteins. The Protein Core also will have limited capacity for large scale protein purification as well as instrumentation to measure surface plasmon resonance and fluorescence for protein characterization. The four Projects of the PPG propose a wide variety of experimental techniques encompassing numerous protein components linked to diverse G protein signaling systems. Many of these avenues of research ultimately will rely on the purification and characterization of recombinantly-expressed proteins. This Protein Core is therefore designed to satisfy these common requirements in an efficient manner using a combination of automation and sophisticated biophysical techniques. By centralizing instrumentation and expertise, the PPG anticipates turning common research needs into a unique opportunity to advance standard biochemical techniques past the era of the individual researcher and into a future of highly-efficient data collection and analysis.